The present invention generally relates to security in network communications.
Digital watermarks are used to enable an individual to add hidden copyright notices or other verification messages to digital audio, video, image signals and documents. For a digital watermark, the message is generally a group of bits describing the information pertaining to the signal or to the author of the signal. The technique is used to add a measure of security to the authenticity of the work without the end user's knowledge or with minimal impact. A simple visual digital watermark could be a seal placed over the image to identify the copyright. The watermark may contain additional information including the identity of the purchaser of a particular copy of material. An invisible watermark might change the least significant bits of the image and be basically imperceptible to the end user but identifiable to the viewer program.
RF watermarking is used to prevent impersonation attacks by modifying the hardware such that the modification can be verified by a node before communication is established. The RF watermark could be an intentional bit time dithering that can be measured before the link is negotiated.
Virtual Private Networks (VPNs) encrypt links between hosts talking over a public network, making it difficult to intercept communications.
Network security on MANet and ad-hoc networks is subject to attacks that can compromise the integrity of the system. Although digital and hardware watermarks help improve the ability to improve the security of the system, they do not provide security against attacks such as the Sybil, Stolen Identity, Invisible Node, Rush, Blackhole, Jellyfish and other common multicast threats. These attacks put information in jeopardy and need to be addressed.